Bottle cap



FIG. 1 is a left side top perspective view of the bottle cap showing my new design;

FIG. 2 is a left side elevational view thereof, the right, front and back views being identical images thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof.

The broken lines are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a bottle cap, as shown and described. 